97 olds 88 computer reset/transmission shifts
#1
Senior Member
Posts like a 4 Banger
Thread Starter
97 olds 88 computer reset/transmission shifts
hey guys,
got an interesting outcome
Ive had my olds 4 years now, it'* had the typical gm 3.8 transmission that goes as quicly as it can into torq converter lockup, most times it seems it'* way too soon, and seems a bit harsh shift when it locks up
also, it'* always been hard to get it to down shift , out of t-c lock up
I ran across a writeup, saying, the pcm/computer is storing drive habits/ data and will go into a limp mode where transmission will pump at full pressure (solenoids in tranny) and will cause transmission harsh shifting and delayed downshift/ t-c unlock issues
if the solenoids in transmission are working ok, this behavior can be reset
I'm thinking...ok..right..but it actually worked!
simply disconnect battery, overnight
odbII scanner will not clear this data , so disconnect battery, over night
reconnect battery, everything is set back to factory new, the computer will relearn idle and driving habbits
result, transmission shifts super smooth, no harsh torq converter lock ups, will unlock and down shift properly..just amazing!
huge differance
wanted to share
got an interesting outcome
Ive had my olds 4 years now, it'* had the typical gm 3.8 transmission that goes as quicly as it can into torq converter lockup, most times it seems it'* way too soon, and seems a bit harsh shift when it locks up
also, it'* always been hard to get it to down shift , out of t-c lock up
I ran across a writeup, saying, the pcm/computer is storing drive habits/ data and will go into a limp mode where transmission will pump at full pressure (solenoids in tranny) and will cause transmission harsh shifting and delayed downshift/ t-c unlock issues
if the solenoids in transmission are working ok, this behavior can be reset
I'm thinking...ok..right..but it actually worked!
simply disconnect battery, overnight
odbII scanner will not clear this data , so disconnect battery, over night
reconnect battery, everything is set back to factory new, the computer will relearn idle and driving habbits
result, transmission shifts super smooth, no harsh torq converter lock ups, will unlock and down shift properly..just amazing!
huge differance
wanted to share
#3
Senior Member
True Car Nut
If the problem returns, you should have codes scanned on the car. The lomp mode as you call itr happens when the computer detects that the shift is taking too long. Then it goes full trancmission pressure and sets a code. Its likely the problem will return. Many are able to work around the issue (bad or flaky pcs) by installing a shift kit.
#4
Senior Member
Posts like a 4 Banger
Thread Starter
was never any codes, just horriable shifting, Ive scanned with odbII scanner..0 codes before or after
but night and day differance in shifting... very pleased...
also, the write up mentioned, there would not be any codes.. and a scanner would not clear any of the data stored for driving habbits/shift
I've tryed to find writeup again...still looking
but it actually worked...
not a little differance...but BIG change
but night and day differance in shifting... very pleased...
also, the write up mentioned, there would not be any codes.. and a scanner would not clear any of the data stored for driving habbits/shift
I've tryed to find writeup again...still looking
but it actually worked...
not a little differance...but BIG change
#5
Senior Member
Posts like a 4 Banger
Thread Starter
1997 Oldsmobile Eighty Eight K = 3.8
I/M Monitors
Since DTCs Cleared
Misfire Monitor ok
Fuel System Mon ok
Comp Component ok
Catalyst Mon ok
Htd Catalyst n/a
Evap System Mon inc
Sec Air System n/a
A/C Refrig Mon n/a
Oxygen Sens Mon ok
Oxygen Sens Htr ok
EGR/VVT Sys Mon ok
=====================
DTCs (Codes)
No codes found
=====================
State OBD Check
MIL Status OFF
Codes Found 0
Monitors OK 7
Monitors Inc 1
Monitors N/A 3
=====================
Record Data
FRAME: -2 TM: -3.6
MIL STATUS Off
ABSLT TPS(%) 0.4
ENG SPEED(RPM) 865
CALC LOAD(%) 3.1
MAF(LB/M) 0.81
MAP("HG) 11.5
COOLANT(°F) 199
IAT(°F) 142
IGN ADV(°) -15.0
ST FTRM1(%) 1.6
LT FTRM1(%) 9.4
VEH SPEED(MPH) 0
FUEL SYS 1 CLSD
FUEL SYS 2 N/A
O2S11(V) 0.850
ST FTRM11(%) 1.6
O2S12(V) 0.450
OBD2 STAT CA
---------------------
I/M Monitors
Since DTCs Cleared
Misfire Monitor ok
Fuel System Mon ok
Comp Component ok
Catalyst Mon ok
Htd Catalyst n/a
Evap System Mon inc
Sec Air System n/a
A/C Refrig Mon n/a
Oxygen Sens Mon ok
Oxygen Sens Htr ok
EGR/VVT Sys Mon ok
=====================
DTCs (Codes)
No codes found
=====================
State OBD Check
MIL Status OFF
Codes Found 0
Monitors OK 7
Monitors Inc 1
Monitors N/A 3
=====================
Record Data
FRAME: -2 TM: -3.6
MIL STATUS Off
ABSLT TPS(%) 0.4
ENG SPEED(RPM) 865
CALC LOAD(%) 3.1
MAF(LB/M) 0.81
MAP("HG) 11.5
COOLANT(°F) 199
IAT(°F) 142
IGN ADV(°) -15.0
ST FTRM1(%) 1.6
LT FTRM1(%) 9.4
VEH SPEED(MPH) 0
FUEL SYS 1 CLSD
FUEL SYS 2 N/A
O2S11(V) 0.850
ST FTRM11(%) 1.6
O2S12(V) 0.450
OBD2 STAT CA
---------------------
#6
Senior Member
True Car Nut
The code it would normally set would be a P1811, but if resetting it fixed what was ailing it, and it stays fixed, enjoy it!
Seldom do you get to enjoy troubleshooting as simple as unplugging it, and then plugging it back in.
Seldom do you get to enjoy troubleshooting as simple as unplugging it, and then plugging it back in.
#7
Senior Member
Posts like a 4 Banger
Thread Starter
thats what i was wondering also, its shift that way the last 4 years, ...
it has never had any codes other than cyl misfires when coil was bad
it drove ok before, with harsh tc lockups...and hard to get it to downshift...
it seemed to always dump it into tc lockup, and motor struggle until you got moving faster....
its been 3 days, and working perfectly... about 300 miles...
i'm waiting for it to go back that way...lol
we did change trans filter/ added lucas trans conditioner in march 2016
maybe the lucas cleaned up what ever was going on... i really dont know
fingers crossed
it has never had any codes other than cyl misfires when coil was bad
it drove ok before, with harsh tc lockups...and hard to get it to downshift...
it seemed to always dump it into tc lockup, and motor struggle until you got moving faster....
its been 3 days, and working perfectly... about 300 miles...
i'm waiting for it to go back that way...lol
we did change trans filter/ added lucas trans conditioner in march 2016
maybe the lucas cleaned up what ever was going on... i really dont know
fingers crossed
#9
Senior Member
True Car Nut
The car does not have a heated catalyst, secondary air injection, or monitor A/C.
#10
Senior Member
True Car Nut
And the stipulations required to complete the evap system tests are fairly extensive, so they are usually the last ones to fall in to place.